Stamp



FIG. 1 is a perspective view showing our new design for a stamp;

FIG. 2 is a left side, right side being a mirror image view thereof;

FIG. 3 is a back elevational view thereof;

FIG. 4 is a front elevational view thereof;

FIG. 5 is a top view thereof; and,

FIG. 6 is a bottom view therof. 

The ornamental design for a stamp, as shown and described. 